Yesterday, the woofer part of one of my pro 80s stopped working. I didn't really think much about it, thought it was a loose connection or something. Today I went out, and neither of the woofers are working, and the horns sound like crap.

My system goes rca input to ws420 to ht4 to pro 80s. I've deduced that its not the ws420, or headphone cord, I have yet to try different rcas, but I think its either something with the amp or crossover in the speakers themselves.

If I change the x over on the amp from hi to full, theres no change, and from full to low, nothing plays.

I'm trying to think if anything unusual has happened recently, but can't think of anything.

I find it odd that 2 speakers have gone out one day after the other. I think the problem is upstream of the speakers themselves. How have you determined its not the EQ? Swapping the in-boat and tower RCA cables at the EQ will tell a lot.

Have you put the amp outputs onto different speakers? Or tried the Pro80s on a different amp..like your interior amp?...
If that doesn't make a difference, open up the pro80 and make sure the crossover is intact...

It would be possible but rare that something upstream in the signal path would allow just the horn tweeters to play but not the midbass speaker, and be common to both channels.
You can substitute a temporary speaker or pull the Pro80 midbass speaker out and access it's terminals directly thereby bypassing the internal passive crossover (please do not do this with a tweeter). This will quickly confirm if the problem is within the speaker or prior to the speaker. This will also bypass the speaker's internal passive crossover and either confirm or eliminate this as a cause.
Keep this in mind. A speaker with a badly burnt voil coil CAN heat up and play until it cools then never play again. If both midbass drivers have burnt voice coils, then this would fit your description. Usage is what they would have in common.
Btw, a horn tweeter, or any tweeter for that matter, played in isolation (all harmonics and no fundamentals) will sound awful. So if the tweeter sounds uncomfortable playing alone that would be expected and by itself means very little.
If you suspect the EQ, however unlikely, simply reverse the inboat and tower zones.
Make sure you confirm good audio grounds on all components and confirm voltage. While these issues may not be the reason for today's inoperative components, this can contribute to problems.

So I went out and hooked just one of the speakers up, and the woofer played for 5ish seconds and then stopped, and I couldn't get it to play again. So I unscrewed the crossover from the housing, and pressed play with just the woofer part of the speaker hooked up. Weirdest thing ever, I could faintly hear the song playing from the crossover. I don't know if thats normal, but I've never heard of that happening.